New shop build, beginning stages with questions

[rangerfredbob]

Life always gets in the way...

I have the corners staked out, I've removed about 10" of dirt from the high end and a few inches from the low part, have a transit but need to get it closer to visibly flat before I get too carried away...

That said, the plans and inspections require no organic matter under the slab, and probably a good idea to remove top soil. The question is how important is it to get top soil out of the way? How much digging do I need to do? I'll be putting gravel under the slab, how deep?

I've been too busy to do research, using a 4000lb 26hp tractor with a 4' bucket, a 4' 5 tooth ripper and a 5' box scraper (no teeth) is not the fastest way to move dirt, and work has been taking up too much time... really need to get the permit process started but want to get the dirt work out of the way first so I have a better foundation started, pardon the pun...

 

[ovrszd]

I removed all topsoil. Then hauled in clay. Got it within a couple inches of flat. Compacted with a sheepsfoot. Made my pad area a lot bigger than my building. Had 20ft of flat grade on all sides past edge of building. The builder said he'd add 12" of elevation with fill material, insulation and 6" slab.

Over estimate rather than under estimate. You only get one chance to build a good pad.

 

[truckdiagnostics]

You do not want water under you slab and any that does get there you want to drain away. Organic material expands when it gets wet. When we put in our pole building we dug out 400 yards of top soil and brought in stone. It is important. You mentioned one area is higher than the other, consider drain tile and clear stone on that edge. I have areas where we do not have the correct drainage under the concrete and it moves every year. We are on clay and it expands big time. Check how your neighbors others in your area have done it. A lot depends on you local conditions on what you can and can not do. What works for one person will not work for someone else. Up north where it is sand, you scrape off the top soil and pour a slab. When we moved down here building on clay was new to me, didn't check around and made mistakes. Check with people in your area that is the best way to go. just my :2cents:
Steve

 

[EddieWalker]

Be sure that you know what topsoil is and identify it properly. I've seen a lot of pictures on here of people removing material that was not topsoil. Topsoil is loam. It's the softer, organic type of dirt that does not compact and is decomposing. Here in East Texas, we do not have topsoil. We just scrape off the grass and start building up the pad with red clay. Do not remove any material that you don't have to. Compacting the new material is very difficult and time consuming.

 

[rangerfredbob]

Making a flat spot is much more difficult than I anticipated, and my tractor is undersized for the undertaking...

Over the summer I got a LOT of dirt moved with my tractor and got everything within 8" apparently (most within ~5") but going the rest of the way takes much more finesse... By far the most time sucking part is just moving dirt around and finding the right place to put it (I found many more low spots in my lawn than I thought I had...). The loader on my tractor is small (if you look up Kwik Way loaders, most are on garden tractors...) so it doesn't hold much dirt in the bucket and hauling that small amount 100 yards takes time, then you gotta get that dirt flat and harrowed, big time suck...

Anywho, my brother offered his Ford 4600 with loader for the weekend and his 48" 3 point tiller to put on my tractor, we spent about 4 hours and the area is expanded a little past the perimiter and all within 2" of being flat and all undisturbed under that level... tomorrow I get to move the 10ish yards of dirt that we dug up today then load the tractor and tiller back up...

I'll be ready for inspections and permitting soon finally! The rain hasn't started yet so I'll wait until that is over before I dig the holes for the posts, I believe the first inspection is for the holes...

As for the drainage concerns, the shop will be on the highest level of my property pretty much, I think I will be renting a trencher at some point to put in electrical and might as well put in some tile though. I believe the plans call for a bunch of gravel so there should be room for expansion. On the soil type apparently according to my brother there is some areas that are down to clay but some are topsoil, we dug out most of the less firm soil though so it should be reasonable.

 

[EddieWalker]

Easy to dig dirt, but it takes a lot to move it any distance.

When I've built pads, I rough it out by dumping the dirt from my bucket and back dragging it. I do this in every direction that I can get my tractor to go. After a few loads I get off the tractor and walk it. That will show my the most obvious areas that need more dirt. I try to get each layer a couple inches thick or less, and I drive over it with the bucket full to cover every inch to compact it with my front tires. Once I get it kind of there by eye, I get out my laser level and spray paint. I either go of the exactly spot I want it all to be, or I walk around and figure out where the most level spots are and put a dot there, and move over 4 feet and mark it plus or minus how many inches I need to change it. Every 4 feet, in every direction will get marked. Then I can get it really close from the seat by dumping and back dragging. It might take me 3 times of measuring to get it ready for concrete.

 

[ovrszd]

Anybody can build a pad. Few can build a flat solid pad. It's an art.

 

[zoedog2012]

Anybody can build a pad. Few can build a flat solid pad. It's an art.

My 80x50 pad cost me 5000$. Done by a pro.

 

[ovrszd]

My 80x50 pad cost me 5000$. Done by a pro.

And if done properly it was worth every penny.

My wife and I built our pad 180x100, sheepsfoot packed, levell within 3", moved 1300 yds of dirt. Have no idea what it would have cost.

 

[rangerfredbob]

Here's some pictures of where I got to this summer and where I ended this weekend... The picture with the 4600 doing work is yesterday with my brother operating and the picture with the 4600 on the trailer is where I ended this weekend. Have the corners marked (the right posts might be hard to see, they have marking paint on the tops) and everything is within 2" and I have a big pile of dirt to figure out what to do with... I'll drag the transit out next weekend (need daylight, could borrow a laser level though...) to measure again but I imagine being within 2" is close enough, the gravel will need to be better but that's easier...

Seeing the corners marked I need to get the transitions on 3 sides a bit further away I'm guessing... How much space should I have flat away from the building? One of the short walls will be on the right of the picture, there's maybe an 18" rise over about 8'. The long wall toward where I took the picture tapers from floor level to that about 18" level and I have maybe a foot from the corners flat at most. I might be over thinking it though as this is just the lowest level, the plans call for 4" of 3/4" minus gravel under the slab and I'll likely be going with a 5" or 6" slab to use my 2 post lift so floor level will be 10" above that and probably a 4" thick gravel entrance for now...